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91.
The feeding activity along the day cycle and the time consumed for extracellular digestion were evaluated in the portunids C. ornatus and C. danae. Swimming crabs were obtained from trawling in Ubatuba bay, São Paulo, Brazil, during both the rainy and dry seasons. In each season, daily scheduled samples were taken at dawn (±6 h), noon (±12 h), dusk (±18 h) and midnight (±24 h). All individuals were dissected and the degree of stomach replenishment was recorded. In order to estimate the time elapsed for extracellular digestion, crabs were fed, and groups were dissected at 30 min intervals to check the conditions of their stomachs. In general, both species show a higher feeding activity during periods of lower light intensity, as evidenced by an increased percentage of full stomachs in dusk and midnight samples. The obtained results support higher feeding activity at night in these species and indicate short time for extracellular digestion, not exceeding 8 h. Nevertheless, full stomachs were recorded in all sampling schedules. In this case, it should be considered that elimination of certain food items such as fish bones, mollusk shells and carapace fragments of crustaceans could take more time than other items. Additionally, some crab species could require a cycle of cell replacement in the midgut gland epithelium until they can take their next meal. 相似文献
92.
This paper focuses on the contributions to natural history, particularly in methods of plant classification of the Portuguese
botanist, man of letters, diplomat, and Freemason Abbé José Correia da Serra (1751–1823), placing them in their national and
international political and social contexts.
Correia da Serra adopted the natural method of classification championed by the Frenchman Antoine-Laurent de Jussieu, and
introduced refinements of his own that owe much to parallel developments in zoology. He endorsed the view that the classification
of plants should be based on the establishment of affinities rather than of differences. The emphasis on affinities went hand
in hand with the development of the concept of symmetry. This idea was introduced by Correia da Serra in systematics and was
adopted and further developed by his friend, Augustin-Pyramus de Candolle. Correia da Serra also argued that Cryptogamia reproduce sexually, advocated extension of methods of comparative anatomy from zoology to botany, and applied them to the
study of fruits.
Correia da Serra was one among many of the estrangeirados, Portuguese``Europeanized' intellectuals who traveled extensively abroad in most cases to escape political or religious
persecution at home. The estrangeirados were important contributors to 18th and 19th century European thinking. Most of the estrangeirados were pivotal in the introduction, dissemination and propagation of the new sciences in Portugal, but unlike most of his fellow
estrangeirados, Correia da Serra was also an innovative man of science in his own right.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
93.
Robinson Ramírez-Vélez Diogo Rodrigues-Bezerra Jorge Enrique Correa-Bautista Mikel Izquierdo Felipe Lobelo 《PloS one》2015,10(10)
Substantial evidence indicates that youth physical fitness levels are an important marker of lifestyle and cardio-metabolic health profiles and predict future risk of chronic diseases. The reliability physical fitness tests have not been explored in Latino-American youth population. This study’s aim was to examine the reliability of health-related physical fitness tests that were used in the Colombian health promotion “Fuprecol study”. Participants were 229 Colombian youth (boys n = 124 and girls n = 105) aged 9 to 17.9 years old. Five components of health-related physical fitness were measured: 1) morphological component: height, weight, body mass index (BMI), waist circumference, triceps skinfold, subscapular skinfold, and body fat (%) via impedance; 2) musculoskeletal component: handgrip and standing long jump test; 3) motor component: speed/agility test (4x10 m shuttle run); 4) flexibility component (hamstring and lumbar extensibility, sit-and-reach test); 5) cardiorespiratory component: 20-meter shuttle-run test (SRT) to estimate maximal oxygen consumption. The tests were performed two times, 1 week apart on the same day of the week, except for the SRT which was performed only once. Intra-observer technical errors of measurement (TEMs) and inter-rater (reliability) were assessed in the morphological component. Reliability for the Musculoskeletal, motor and cardiorespiratory fitness components was examined using Bland–Altman tests. For the morphological component, TEMs were small and reliability was greater than 95% of all cases. For the musculoskeletal, motor, flexibility and cardiorespiratory components, we found adequate reliability patterns in terms of systematic errors (bias) and random error (95% limits of agreement). When the fitness assessments were performed twice, the systematic error was nearly 0 for all tests, except for the sit and reach (mean difference: -1.03% [95% CI = -4.35% to -2.28%]. The results from this study indicate that the “Fuprecol study” health-related physical fitness battery, administered by physical education teachers, was reliable for measuring health-related components of fitness in children and adolescents aged 9–17.9 years old in a school setting in Colombia. 相似文献
94.
Diogo N. Silva Sebastien Duplessis Pedro Talhinhas Helena Azinheira Octávio S. Paulo Dora Batista 《PloS one》2015,10(12)
Understanding the origin and evolution of pathogenicity and biotrophic life-style of rust fungi has remained a conundrum for decades. Research on the molecular mechanisms responsible for rust fungi evolution has been hampered by their biotrophic life-style until the sequencing of some rust fungi genomes. With the availability of multiple whole genomes and EST data for this group, it is now possible to employ genome-wide surveys and investigate how natural selection shaped their evolution. In this work, we employed a phylogenomics approach to search for positive selection and genes undergoing accelerated evolution at the origin of rust fungi on an assembly of single copy genes conserved across a broad range of basidiomycetes. Up to 985 genes were screened for positive selection on the phylogenetic branch leading to rusts, revealing a pervasive signal of positive selection throughout the data set with the proportion of positively selected genes ranging between 19.6–33.3%. Additionally, 30 genes were found to be under accelerated evolution at the origin of rust fungi, probably due to a mixture of positive selection and relaxation of purifying selection. Functional annotation of the positively selected genes revealed an enrichment in genes involved in the biosynthesis of secondary metabolites and several metabolism and transporter classes. 相似文献
95.
Carolina David Wiener Karen Jansen Gabriele Ghisleni Manuella Pinto Kaster Luciano Dias de Mattos Souza Diogo Rizzato Lara Luiz Valmor Portela Ricardo Azevedo da Silva Jean Pierre Oses 《Neurochemical research》2013,38(7):1394-1398
Several biological factors have been recently related with major depression and bipolar disorder. The aim of our paper was to investigate the peripheral levels of the protein neuronal specific enolase (NSE), a putative marker of neuronal damage, comparing patients with major depressive disorder and bipolar disorder to control subjects. This is a case–control study nested in a cross-sectional population-based survey. Psychopathology screen was performed using the Mini-International Neuropsychiatric Interview 5.0 and blood samples were collected from 108 young adults. Three groups were selected, 36 healthy controls, 36 subjects with major depression disorder and 36 subjects with bipolar disorder. Serum levels of NSE significantly decreased (p = 0.002) in major depression disorder (2.19 ± 1.78 ng/mL) and bipolar disorder subjects (2.53 ± 2.61 ng/mL) compared to the control group (3.55 ± 2.19 ng/mL). In conclusion, peripheral neuronal specific enolase may be a useful marker drug-naïve major depression disorder and bipolar disorder, but its pathophysiological significance and response to treatment should be further investigated. 相似文献
96.
Olivia U Mason Nicole M Scott Antonio Gonzalez Adam Robbins-Pianka Jacob B?lum Jeffrey Kimbrel Nicholas J Bouskill Emmanuel Prestat Sharon Borglin Dominique C Joyner Julian L Fortney Diogo Jurelevicius William T Stringfellow Lisa Alvarez-Cohen Terry C Hazen Rob Knight Jack A Gilbert Janet K Jansson 《The ISME journal》2014,8(7):1464-1475
The Deepwater Horizon (DWH) oil spill in the spring of 2010 resulted in an input of ∼4.1 million barrels of oil to the Gulf of Mexico; >22% of this oil is unaccounted for, with unknown environmental consequences. Here we investigated the impact of oil deposition on microbial communities in surface sediments collected at 64 sites by targeted sequencing of 16S rRNA genes, shotgun metagenomic sequencing of 14 of these samples and mineralization experiments using 14C-labeled model substrates. The 16S rRNA gene data indicated that the most heavily oil-impacted sediments were enriched in an uncultured Gammaproteobacterium and a Colwellia species, both of which were highly similar to sequences in the DWH deep-sea hydrocarbon plume. The primary drivers in structuring the microbial community were nitrogen and hydrocarbons. Annotation of unassembled metagenomic data revealed the most abundant hydrocarbon degradation pathway encoded genes involved in degrading aliphatic and simple aromatics via butane monooxygenase. The activity of key hydrocarbon degradation pathways by sediment microbes was confirmed by determining the mineralization of 14C-labeled model substrates in the following order: propylene glycol, dodecane, toluene and phenanthrene. Further, analysis of metagenomic sequence data revealed an increase in abundance of genes involved in denitrification pathways in samples that exceeded the Environmental Protection Agency (EPA)''s benchmarks for polycyclic aromatic hydrocarbons (PAHs) compared with those that did not. Importantly, these data demonstrate that the indigenous sediment microbiota contributed an important ecosystem service for remediation of oil in the Gulf. However, PAHs were more recalcitrant to degradation, and their persistence could have deleterious impacts on the sediment ecosystem. 相似文献
97.
Optimal escape theory states that animals should counterbalance the costs and benefits of flight when escaping from a potential predator. However, in apparent contradiction with this well-established optimality model, birds and mammals generally initiate escape soon after beginning to monitor an approaching threat, a phenomena codified as the “Flush Early and Avoid the Rush” (FEAR) hypothesis. Typically, the FEAR hypothesis is tested using correlational statistics and is supported when there is a strong relationship between the distance at which an individual first responds behaviorally to an approaching predator (alert distance, AD), and its flight initiation distance (the distance at which it flees the approaching predator, FID). However, such correlational statistics are both inadequate to analyze relationships constrained by an envelope (such as that in the AD-FID relationship) and are sensitive to outliers with high leverage, which can lead one to erroneous conclusions. To overcome these statistical concerns we develop the phi index (Φ), a distribution-free metric to evaluate the goodness of fit of a 1∶1 relationship in a constraint envelope (the prediction of the FEAR hypothesis). Using both simulation and empirical data, we conclude that Φ is superior to traditional correlational analyses because it explicitly tests the FEAR prediction, is robust to outliers, and it controls for the disproportionate influence of observations from large predictor values (caused by the constrained envelope in AD-FID relationship). Importantly, by analyzing the empirical data we corroborate the strong effect that alertness has on flight as stated by the FEAR hypothesis. 相似文献
98.
99.
100.
Cássio S. Meira José Maurício dos Santos Filho Caroline C. Sousa Pâmela S. Anjos Jéssica V. Cerqueira Humberto A. Dias Neto Rafael G. da Silveira Helena M. Russo Jean-Luc Wolfender Emerson F. Queiroz Diogo R.M. Moreira Milena B.P. Soares 《Bioorganic & medicinal chemistry》2018,26(8):1971-1985
4-(Nitrophenyl)hydrazone derivatives of N-acylhydrazone were synthesized and screened for suppress lymphocyte proliferation and nitrite inhibition in macrophages. Compared to an unsubstituted N-acylhydrazone, active compounds were identified within initial series when hydroxyl, chloride and nitro substituents were employed. Structure-activity relationship was further developed by varying the position of these substituents as well as attaching structurally-related substituents. Changing substituent position revealed a more promising compound series of anti-inflammatory agents. In contrast, an N-methyl group appended to the 4-(nitrophenyl)hydrazone moiety reduced activity. Anti-inflammatory activity of compounds is achieved by modulating IL-1β secretion and prostaglandin E2 synthesis in macrophages and by inhibiting calcineurin phosphatase activity in lymphocytes. Compound SintMed65 was advanced into an acute model of peritonitis in mice, where it inhibited the neutrophil infiltration after being orally administered. In summary, we demonstrated in great details the structural requirements and the underlying mechanism for anti-inflammatory activity of a new family of hydrazone-N-acylhydrazone, which may represent a valuable medicinal chemistry direction for the anti-inflammatory drug development in general. 相似文献